(t+2)⋅(t−9)−t2 = t2-9t+2t-18-t2 = -7t-18,
-7t-18, при t= -10
-7 ⋅ (-10) - 18 = 70-18= 52
ответ: 52
(10+2)*(10-9)-10*2
1)10+2=12
2)10-9=1
3)12*1=12
4)10*2=20
5)12-20=-8
(t+2)⋅(t−9)−t2 = t2-9t+2t-18-t2 = -7t-18,
-7t-18, при t= -10
-7 ⋅ (-10) - 18 = 70-18= 52
ответ: 52
(10+2)*(10-9)-10*2
1)10+2=12
2)10-9=1
3)12*1=12
4)10*2=20
5)12-20=-8